Projector lamp



Filed Sept. 21, 1955 s Sheets-Shet 1 INVENTO RS J HN E M fil/LEY Guy f?TREVILLIHN JUL Mk7 THE'lRATfORNEY W .7 7 I a 1 W w w w i M I 1 v H e .1I 7 .24? I ,y w M L 7 w 9 pi Nov. 2, 1937. J. E. MCAULEY ET AL 2,997,767

' PROJECTOR LAMP Filed Sept. 21, 1935 3 Sheets-Sheet 2 INVENTORS JEMF/YumyiQ GUYR TkEV/LL/HN THf/H ATTORNEY Nova 2, i937.

J. E. M AULEY ET AL PROJECTOR LAMP Filed Sept. 21, 1935 5 Sheets-SheetI5 Q l SYN mEm 3 M mfiw v N N fi m J E w a W w J68 r 7 Patented Nov. 2,1937 2,097,767

UNITED STATES PATENT OFFICE PROJECTOR LAMP John E. McAuley and Guy R.Trcvillian, Chicago,

111., assignors to J. E. McAuley Mfg. 00., Chicago, 111., a corporationof Delaware Application September 21, 1935, Serial No. 41,551

' 19 Claims. (01. 176-51) This invention relates to projector lamps ofthe and to the rear of the mirror 6, there is mounted high intensity aretype, especially adapted for the .the major portion of the negativeelectrode holder projection of motion pictures. The principal oband apermanent magnet l2; the negative elecjects of the invention are tosimplify the structure trode 8 and the finger 9, which supports the for-5 of such lamps so as to permit ready access to the ward portion thereofand forms a part of the 5 electrode holders for recarboning, adjustment,holder, projecting through a central aperture in cleaning of thereflector, and other purposes. in the mirror. Magnet l2, in combinationwith Another object is to provide an improved octhis type of highintensity arc, forms the subject culter or light extinguishing shutterof simple, matter of my prior application for Letters Patent,

' but effective construction, which in its inoperative Serial No.26,117, filed June 12, 1935, and is not 10 position lies entirelywithout the projected beam. claimed herein. The member 9 is providedwith Other purposes will be apparent as the descripa V-shaped notch atits forward end and is setion proceeds. cured to the supporting bracket13, which is ad- Referring to the drawings disclosing the prejustablysecured to fixed bracket 95. Slidably ferred form of our invention.mounted on bracket 13 with a loose fit is a rack 15 Fig. 1 is a sideelevation of my projector lamp bar 14 which may be moved back and forthbya with a portion of the side door and top removed to pinion l5 meshingtherewith on shaft I6. At the h th interi there f, rear end of the rackl4 we provide a short spring Fig. 2 is an enlarged plan view of theshutter or 33 which normally holds the rack slightly eleocculter in theraised or inoperative position. vated at the rear, but which permitsadjustment 20 Fig. 3 is a detail of the operating cams for the thereofto align the two electrodes. The negasame. tive electrode is gripped tothe rear of the arcing Fig. 4 is a rear elevation of the projector lamptip by cam surfaces 34 on a shaft 35. By rotating with the rearmost dooropenor cut away. the handle 36 thereon, the electrode is gripped or Fig.5 is a perspective view of the rear portion released at will. Theposition of the holder may 25 of the lamp, showing both the rear doorand the also be adjusted by loosening the nut 31 and tumintermediatehinged part open. ing the pin 38 by which an eccentric 39 within theFig. 6 is a diagrammatic plan view showing how bracket I3 is turned toraise or lower or displace both electrodes are fed from the same motor.said bracket, in which the rack bar I4 is slidably Fig. 7 is a sideview, partly in section, of the mounted. v 30 positive electrode holder.For hand adjustment, feed shaft to may be Fig. 8 is a similar view ofthe lower portion turned by a knob H on a shaft 16 connected to thereoffrom the opposite side. shaft 16 through a universal joint l8. The shaftFig. 9 is a side elevation, partly in section, of i6 is also fedautomatically from a feed motor 20, 5 the negative electrode holder.which also preferably feeds the positive electrode,

Fig. 10 is a detail of the feeding ratchet for the but the drivingconnection or coupling between negative electrode. the negative feed andmotor is such that it only Fig. 11 is another detail of the same, takenat requires juxtaposition to transmit power. In right angles to Fig. 10and showing the pawl or other words, the entire hinged member 5 may beclutch rings in section. swung open without disconnecting any parts, and40 Fig. 12 is a detail of the operating means for the as soon as it isclosed again the power transmitocculter. ting coupling is operative.Such a mechanlsm'is The entire lamp is enclosed within a main housshownas in the form of an arm 21 pivoted at 22 mg I provided with side doors2 which may be and reciprocated by the engagement of a recipraised, togive access to the positive carbon, on rocatory shaft 23 with the lowerend of said arm. hinge rods 3 running along each side of the top ofPreferably an adjustable set screw 24 is mounted the structure. At theback of the lamp housing at the lower end of the arm so as to vary therelaor drum I, we provide an outer hinged door 4 and tive amount of lostmotion between said parts, to an inner section 5 also hinged on commonhinge vary the stroke and rate of feed of the negative. pins 99, 99',the latter serving as a mounting both The arm 2| is normally biased by acoil spring for the reflector or projector 6 and for the entire 25 totend to close contact between parts 23 and negative electrode holder 1and its operating 24, but the forward advance may be limited by a means.By this construction the lamp structure front plate Said arm isconnected at its r may be opened up .7 (see Fig. 5), the reflector upperend to a ring 26 in which is mounted a cleaned and inspected, etc.Within this member ratchet-or one-way clutch device engaging the 66.

drum 21, loosely mounted on the feed shaft I 6 and coupled thereto by aslip friction clutch comprising a disc I pinned to shaft l6 and anopposite disc 50! spring pressed by spring I02 to clamp drum 2'!therebetween. An inclined recess 28 is provided within the ring 26, inwhich is a spring pressed roller 29 which will grip the drum when thering is rotated in one direction, but release it when said ring isrotated in the other direction.

Owing to the small amount of power transmitted and the small friction ofthe system, we

find it preferable to provide a second ratchet,

mechanism to prevent the drum from turning backward during the returnstroke of the main 7 pawl or clutch ring. To this end, there is shown asecond ring 39 which is prevented from rotating by a fixed pin SI andwhich has a similar pawl clutch 32 operating to prevent reverse movementof drum 21. Slip friction clutch IOU-l0! is relatively weak so that knobH may be turned in either direction for hand feed by slipping theclutch. Y

The said shaft 23 is reciprocated from the driving motor 20 by means ofa cam 42 mounted on a transverse shaft 43 rotated from the motor 20 byany suitable gearing, such as worm M and worm wheel 45. The same shaft43 may rotate the feed screw 45 for the positive electrode holder,actuating the same through suitable gearing such as helical gearing l!and spur gearing 38.

i For slow hand feeding there may be provided a knob 49 which may bepushed in against the axial spring 50, abutting at its outer end againstfixed plate 50', to engage the teeth on clutch i and turn the shaft 63,this being permitted by providing a second clutch l I 0 between shaft'33 and a sleeve Hi, which is released when clutch 5! is closed by pushrod I I2 within the sleeve,

-so that the positive feed may be manually adjusted without interruptingthe automatic negative feed.

Ventilation for the negative holder and mir- I ror is provided by aninlet M4 at the bottom behind the mirror so that the cooling air willnot disturb the arc. The air rises behind the mirror around the negativeholder and emerges through an outlet 82 at the top which, when thehinged part 5 is closed, registers with a chimney 83 in the fixedhousing, the hot air escaping through the grill work 84 therein. Fig. 4shows how the negative holder is readily accessible for recarboningmerely by opening back door 4, since it lies mainly to the rear of thereflector mirror.

The positive holder :52 is shown as slidably mounted on track rods t6and 53 within the lamp box and is normally fed byathe rotation of onerod 46, formed as a, feed screw. Means are provided, however, for quickadjustment of the positive electrode by releasing it from the feed screwand sliding it directly along the trackway. For this purpose there isshown mounted on the lower part of said holder a pinion 56, the threadsof which normally register with the threads on the feed screw and whichis normally fixed against rotation, but is releasable at will. To thisend, the pinion is journaled between a pivoted jaw '59 and a fixed part59'. A lever 55, on the shaft 56 of which is an eccentric 51, serves toraise a block 58 upwardly to rock the lever 59 upwardly against theaction of spring 60 and about its pivot 6!. This action lowers theopposite end of the lever with respect to said pinion so as to free thelocked pinion and permit it to freely rotate on its own axis. Underthese conditions, it will be seen, the positive electrode may be readilyslid along the trackway by hand without rotating the feed screw.

The positive electrode is clamped to the rear of the are between a fixedupper jaw 62 and a movable lower jaw 63 which also serves to introducecurrent to the arc, the latter being operated by rotating the threadedshaft 6 5 on which the lower jaw is mounted, the shaft being threaded ina bracket 65 pivoted at 66 on a fixed support 61, the parts having aloose fit as in the negative holder. It will readily be seen, therefore,that a movable support is also provided forthe rear portion of thepositive electrode holder so as to facilitate the alignment of the tipthereof, the forward portion resting within a V-shaped notch 68 in afixed guide 69, regardless of irregular shaped electrodes, that is,imperfect or crooked. The loose fit of the holder supports of bothelectrodes permits exact alignment for the tips of both electrodes bythe V-shaped guides 9 and l8 adjacent the forward ends thereof. This isof especial advantage with the long,- thin electrodes employed in themodern high intensity projector lamp. Said guide lies adjacent thepositive crater and is shown as provided with a vertical channel '10 toguide the particles and ashes dropping from the electrode into theremovable catch pan H.

For preventing damage to the reflector during thestriking of the arc andalso for occulting purposes, there is shown a pair of complementary,substantially semicircular shutters l2 and 12' which, in the occultingposition, lie between the positive crater and the mirror so as tointercept any stray ho't particles from the arc and to cut off the lightfrom the crater to the mirror. As shown, they lie to each side of thenegative tip, a cut out portion E92 and H12 being provided in each forthe electrode. Each of said shutters is mounted on an arm 13 which hassecured thereto a short shaft 15 journaled in a cross bar M which, inturn, is journaled for rotation about a transverse axis on-trunnions 95and 96'. On the upper end of said shafts 15 are secured cam members 16and 76' which operate to turn the shafts 15, through a substantial angleas the arms 13 are raised about axis 96-96 due to the engagement of thecams with stops 9! which rotate the same against the action of tensionspring 90. By this, or similar, means the shutters clear the positiveelectrode holder 69 as they are swung upwardly. For operating theocculter or.

douser, said bar 74 is provided with an upwardly extending arm or neckI! which is engaged by a long lever 18 extending to the front of thelamp and operating from a handle member 19 pivoted at 80. By throwingsaid handle down into the dotted line position, the bar 78 is pushed tothe rear and raised at its forward end into the dotted line position,thus rocking the arms TI about their pivots BI and rotating the shuttersthe film when the arc is occulted, we have shown an auxiliary forwardshield 85 in the form of an arc shaped member which closes the frontopening or door 86 of the lamp. Said member is con-' nected by link 87with thehandle 19, so that it is closed at the same time the arc isocculted and opened when the occulter is moved to the upper position.

It should be observed that all operating and adjusting handles aremounted on the same side of the drum. These handles include the handleII for operating the negative feed, the handle 49 for the slow positivefeed, and the handles 88 and 89 for ad usting the mirror either backwards or forwardly, or the inclination thereof.

We also provide in the top of the drum a slot 92 by which some of thelight within the drum emerges to illuminate a glass name plate 93, thelight appearing to make the same luminous since the letters are etchedin the glass.

1' As many changes could be made in the above construction and manyapparently widely different embodiments of this invention could be madewithout departing from the scope thereof, it is intended that all mattercontained in the above description or shown in the accompanying drawingsshall 'be interpreted as illustrative and not in a limiting sense.

Many advantages are secured by this invention, which will be obvious tothose skilled in the art. Thus, the releasable feed pinion 54 willoutlast a fixed jaw or pin, since the teeth in engagement with the screware frequently changed. Also, it will not jam when the end of thethreads 46 is reached, but will positively stop the feed.

Having described our invention, what we claim and desire to secure byLetters Patent is:

1. In a projector lamp, a pair of complementary shields normally lyingin operative position to each side of the negative electrode to protectthe mirror during striking of the are, means for pivoting said shieldsat the top of the lamp, operating means for rotating said shields to lieat the top of the lamp, and means for simultaneously turning saidshields to clear the lamp parts.

2. A projector lamp comprising a main housing, a hinged part at the rearthereof, an electrode holder and feeding mechanism mounted within saidpart, a motor for feeding both electrodes mounted on said housing, and atwo-part coupling between said motor and said mechanism requiring onlyjuxtaposition to transmit power.

3. A projector lamp comprising a main housing,

a hinged part at the rear thereof, anelectrode holder and feedingmechanism mounted within said part, a mirror also mounted in said part,a 2

second elect-rode holder and feeding mechanism mounted in said housing,and a common power means for driving both feeding means.

4. A projector lamp comprising a main housing, a hinged part at the rearthereof, an electrode holder and feeding mechanism mounted within saidpart, a reflector also mounted in said part, a second electrode holderand feeding mechanism mounted in said housing, and a hinged door to therear of said part, whereby the first named electrode may be trimmed fromthe rear of the reflector;

5. In a projector lamp, a clamping carriage for an electrode, a feedscrew for feeding the carriage and electrode, power means for rotating.said screw for normal feed, a locked pinion on said carriage with whichsaid screw meshes for normal feeding, and means for releasing saidpinion for rapid adjustment of said carriage.

6. In a high intensity are projector lamp having horizontally arrangedelectrodes, a clamping means for the rearward portion of each electrode,a fixed guide for the forward portion of each electrode, and meanspermitting limited play or movement of said clamping means to preventmisalignment of the electrode tips due to imperfect or crookedelectrodes.

7. In an automatic projector lamp feed, a reciprocating part, a feedshaft for feeding an electrode, a one-way clutch'for connecting saidpart and shaft, including a driven drum part, a second one-way clutchconnecting said shaft and a fixed part and acting on said drum to assurestep by step advancement of said shaft, a slip friction clutch betweensaid drum and shaft, and a manual means for turning said shaft fordirect adjustment of the electrode in either direction, said last namedclutch permitting said manual feeding of the electrode.

8. A projector lamp comprising a main housing, a reflector mountedtherein, an electrode holder and its support mounted in front of saidreflector, a second electrode holder at the rear of said reflector, theforward portion thereof projecting through a hole in said reflector, anda rear door hinged on said housing whereby said second mentioned holdermay be recarboned without moving the reflector.

9. A projector lamp comprising a main housing, a hinged part at the rearthereof, an electrode holder and feeding mechanism mounted within saidpart, a motor for feeding both electrodes' mounted on said housing, ashaft reciprocated by said motor, a pawl'or clutch member oscillatedthereby for operating -said feeding mechanism, and an adjustable memberbetween said shaft and member to vary the stroke of the latter for eachreciprocation of said shaft.

10. A projector lamp comprising a main housing, a reflector, anelectrode holder in front of said reflector, a second electrode holdermounted at the rear of said reflector, the forward portion thereofprojecting through a hole in said reflector, a rear door hinged on saidhousing whereby said second mentioned holder may be recarboned' fromthe-rear of the reflector without moving the reflector, said reflectorand rear electrode holder both being mounted in a second hinged part atthe rear of said housing and which may be opened for inspection andcleaning of the reflector.

11. In a projector lamp having a housing, an electrode holder, a feedscrew for feeding the same, power means for rotating said screw,alternative hand means also for rotating said screw, a normally lockedpinion on said holder with which the threads of said screw engage forimparting the feed, and means for releasing said Y pinion to permitquick sliding of said holder.

'12. In a projector lamp having a housing and a mirror, a pair ofcomplementary disc-like shields adapted in operative position to lie toeach side of the negative electrode to protect the mirror duringstriking of the arc and to cut off light between the positive crater andthe mirror when the lamp is lit, means'for pivoting said shields nearthe wall of the lamp housing, operating means for rotating said shieldsto lie adjacent a wall of the housing outside of the reflected beam, andmeans for simultaneously turning said shields about a second axis toclear the lamp Da ts.

13. A projector lamp comprising a main housins, a hinged part at therear thereof, an electrode holder and feeding mechanism mounted withinsaid part, including a reciprocating memher and a one-way clutch, amirror also mounted common power means for driving both feeding means.

14. In a high intensity are projector lamp having horizontally arrangedlong, thin non-rotating electrodes, a clamping means for the rearwardportion of each electrode by which current is led into the electrodes, afixed guide for the forward portion of each electrode, and meanspermitting limited play or movement of said clamping means to preventmisalignment of the electrode tips due to imperfect or crookedelectrodes.

15. In a projector lamp having a housing, a mirror and an electrodeholder within said housing, a pair of complementary shields adapted inoperative position to lie to each side of the negative electrode toprotect the mirror during the striking of the arc and to cut off lightbetween the positive crater and the. mirror when the lamp is lit, meansfor pivoting said shields outside of the reflected beam, and operatingmeans for rotating said shields to lie outside of the reflected beam.

16. A projector lamp comprising a main part, a hinged part at the rearthereof, an electrode holder and feeding mechanism mounted within eachof said parts, a motor for feeding both electrodes mounted on one ofsaid parts, and a separable two-part coupling between said motor andsaid mechanism in the other part requiring only juxtaposition totransmit power from said motor to said feeding mechanism.

17. A projector lamp comprising a main housing, a reflector mountedtherein, an electrode holder and its support mounted in front of saidreflector, a second electrode holder and its support mounted at the rearof said refiector, the electrode supported thereby extending through ahole in said reflector, a guide for the forward end of said electrode infront of said reflector, and a rear door hinged on said housing wherebysaid second mentioned electrode holder may be recarboned without movingthe reflector.

18. In a feeding means for an electrode of arc lamps, a clutch drum,similarly acting one-way clutch members acting on said drum, power meansfor oscillating one of said clutch members through a variable stroke tofeed the electrode step by step, said other clutch member beingrelatively stationary during the return stroke of the first mentionedclutch member, an electrode feed member, and a slip friction connectionbetween said drum andsaid feed member, whereby said electrode may be fedby hand in either direction.

19. In a' feeding means for an electrode of projector lamps, a clutchdrum, 2. one-way clutch acting on said drum, power means for oscillatingsaid clutch through a variable stroke to rotate said drum step by step,a feed shaft on which said drum is loosely mounted, a. pair of frictiondiscs on opposite sides of said drum and frictionally gripping the same,at least one of said discs being secured to said feed shaft, and handmeans for also turning said shaft for hand feeding of the electrode.

JOHN E. MCAULEY. GUY R. TREVILLIAN.

